1. Field of the Invention
The present invention relates to the conversion of tertiary alkanols such as tertiary butyl alcohol to oligomers of the corresponding iso-olefin in a one-step liquid phase process using a homogeneous catalyst such as methane sulfonic acid.
2. Description of the Prior Art
The dehydration of tertiary alkanols such as tertiary butyl alcohol to the corresponding olefin is a well known reaction. See, for example, U.S. Pat. Nos. 5,475,183, 3,665,048, and the like. Catalysts such as alumina, methane sulfonic acid, and the like have been used.
Further, it is known that tertiary alkanols such as tertiary butyl alcohol can be directly converted to oligomers of the corresponding iso-olefin in one step using solid heterogenous catalysts such as zeolite Beta. See U.S. Pat. No. 5,157,192.
There are, however, problems associated with the heterogeneous catalyst systems. Product separation is a problem as is control of the reaction and the removal of heat in heterogeneous systems. In addition, condensation products tend to accumulate on the solid catalyst surfaces leading to a rapid decline in catalyst activity and the necessity for frequent reactivation.